EFFECTS OF MORPHOLOGIC RESTENOSIS, DEFINED BY MRI AFTER COARCTATION REPAIR, ON BLOOD-PRESSURE AND ARM-LEG AND DOPPLER GRADIENTS

Ten years after coarctation repair, 36 adolescents and young adults we re studied in order to evaluate the relationship of anatomy at the res ection site to blood pressure and arm-leg and Doppler gradients. The p atients underwent magnetic resonance imaging (MRI), exercise testing, and continuous wave (CW) Doppler echocardiography. On MRI, residual na rrowing at the resection site was measured as 1-(0 anastomosis/O desce nding aorta) and expressed as percent stenosis. Residual stenosis on M RI was negatively correlated with the leg pressure at rest (P=0.0003) and during exercise (P=0.002). Residual stenosis correlated positively with the arm-leg gradient at rest (P<0.0001) and during exercise (P<0 .0001) and with the peak CW Doppler gradient across the anastomosis (P <0.0001). However, residual stenosis was not related to the systolic b lood pressure of the arm at rest or during exercise. The systolic arm pressures did not differ between patients with residual stenosis of le ss than 30% (group I), patients with residual stenosis of equal to or greater than 30% but less than 45% (group II), and patients with resid ual stenosis of equal to or greater than 45% (group III). In conclusio n residual anatomic stenosis influences blood pressure in the legs, th e arm-leg gradient, and the Doppler gradient across the anastomosis. A rm hypertension late after coarctation repair seems not to be related to residual stenosis, and the benefit of reintenvention in these patie nts remains questionable.